Etching apparatus.



L. E. -& H. S. LEVY.

ETCHING APPARATUS.

APPLlCATlON FILED MAY19, 1911.

1,137,339. Patented Apr. 27, 1915.

2 SHEETS-SHEET 1.

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THE NORRIS PETERS 60.. PHOTO-LITHQ. WASHINGTON. D. CT

2 SHEETS-$HEET Z Patented Apr. 27, 1915;

.L. E. & H. S. LEVY.

ETCHING APPARATUS APPUCAHON FHED MAYI9,|9IL

000000000000 OOOOOOOOOOOO OOOOOOOOOOOO THE NORRIS PETERS 50., PHOTDVLITHOH WASHINGTON, D C.

- production of etched sr'rns n FLOUIS E. LEVY AND HOWARD S. LEVY, 0F PHILADELPHIA, PENNSYLVANIA; SAID LOUIS E. LEVY ASSIGNOR T0 GRAPHIC ARTS COMPANY, OF PHILADELPHIA, PENNSYLVANIA, A CORPORATION OF DELAWARE.

E'ICI-IING APPARATUS.

Specification of Letters Patent.

Patented Apr. 2'7, 1915.

Application filed May 19, 1911. Serial No. 628,322.

To all whom it may concern:

'Be it known'that'we,LoU1s E. LEVY and HOWARD S. LEVY, citizens of the United States, residing at Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented certain new and useful Improvements in Etching Apparatus, of which the following is a specification.

. This invention relates to improvements in etching apparatus or machines, the purpose being to efficiently etch metal plates for "use in the printing art, more particularly in the plates for photo-engraved reproductions, and in such an apparatus as we have devised the plate to be etched is maintained in a bath of etching fluid, which fluid is agitated by the passage of air therethrough, the air contacting with the surface to be etched to constantly bring diflerent new particles of the etching fluid in contact with thesurface to be etched, and to remove fromthe platethe etching fluid that was in previous contact therewith.

Another purpose of our invention is to provide an etching apparatus in which is embodied means of such construction that air pressure is reduced above a part of the surface of the etching fluid so that the pressure of the atmosphere upon other portions of the surface of the etching fluid will force or draw air through the etching fluid to agitate the same so that the etching fluid will lave the surface of the plate to be etched, the arrangement of the parts being such that the etching fluid which is satu rated with the metal removed from the etched plate will be at the bottom of the tank and will not be disturbed by the ebullitions eflected by the reduction of the pressure of air upon the surface of the etching fluid.

Our invention may be practised by means of the apparatus shown by the accompany ing drawings, though we do not limit our invention to the details illustrated thereby, the drawings merely showing one form of apparatus. V

Figure 1, is a front elevation and section, such view showing the .plate carrier in position to receive the plate. Fig. 2, is a detail view showing a front elevation and section. of the lower portion of the apparatus that 2, and upon blocks placed within the tub is an acid-tank or receptacle 3. The acid tank is. preferably made of acid-proof material and its bottom being shaped to have a raised central portion 4 sloping down toward the rightand left sides and curved portions that connect the upward projecting portion with the vertical side walls of the acid tank. The casing 5, may be constructed to receive this tank 3, or the casing may be made up to fit over or receive'the tank and when thetank and casing are assembled for use the inner wall 6 of the outer flue 'Z will depend into the tank 3 below the normal level of the etching fluid which is placed therein.

The casing 5 is made to provide two conduits or flues 7 and 8 on each of the sides of the apparatus, the outer flues 7 having inner walls 6 that serve as the outer walls of the inner flues 8, and the walls 6 depend and have their lower portions bent-inward to provide a ledge 9 or support for a perforated plate 10. The inner section or portion of the casing has an opening therethrough, located above the perforated plate 10, such opening being surrounded by a ledge or flange 11 that provides a rest for a plate 12, to which a block 13 is secured, the block having means for attaching thereto the plate to be etched. The ledge 11, plate 12,. block 13 and the plate 14 that is to be etched are so positioned relative to one another and to the perforated plate 10 that is maintained inimersed in the tank 3, that the plate 14 will be submerged in the etching fluid contained by the tank 3. The inner portion of the casing having the flues 8 is practically air tight when the plate carrier rests upon the ledge 11, and the flues 8 are connected by a chamber having a pipe 15 that leads to a suction fan 16 or other suitable means for exhausting air and the gaseous products giving off during the process of etching, as the walls 6 that depend below the level of the etclliing fluid in the tank 3 make a liquid sea i V The outer flues 7 above the level of the fluid in the tank 3 need not necessarily be fluid, or the front of. the lower portion of the casing, is provided with means for attaching thereto a rock shaft 18' which turns in its attaching means, this bar 18 having secured thereto a section or part 19 one edge thereof being bent at right angles for attaching thereto by suitable hinges the plate 12. The rock shaft 18 has aflixed thereto, at one end, a handle 20 by which the plate 12 is operated so that it may be positioned to rest within the casing upon the flanges 11. or outside of the casing with the plate to be etched in an inclined position above the tub 1.

In order to provide means for readily Washing the plate 1st after it has been partially-or completely etched, the front portion of the casing has attached thereto a Water supply pipe 21 to which branch pipes are secured, these branch pipes 22 and an intermediate portion 23 of the supply pipe 21 being perforated so that when it is desired to wash the plate streams or jets of water will be projected upon the plate. The perforated plate 10, is preferably provided with apertures or openings which increase in size from the center portion of the plate to the sides, as shown by Fig. 6, the central or smaller perforations being above the highest or central portion of the tank 3, and the larger openings being adjacent to the sides where the air is caused to pass into the etching fluid placed in the tank 3. V

As heretofore intimated the construction of the casing 5 may be varied from that shown, and if desired the air inlet fines or ways may be dispensed with, as not essential to the practical operation of the etching apparatus, and the tank 3 instead of having a bottom with a centrally curved portion may I have as a'substitute therefor a plate which is bent along its center to provide inclined sides the ends thereof resting upon the flat bottom of the tank.

In operation etching fluid is placed in the tank 3 by pouring the same through the opening that is closed by the door that carries the plate-holder, to which the plate to be etched is attached by suitable clampstor other means, and sufficient etching fluid is placed in the tank to submerge the plate when the door is positioned to close the opening. lhe door or plate 12 rests upon the ledge or flangell and either the door or flange may be provided with suitable packing to assist informing a tight joint. When the exhaust fan is started a partial vacuum will be produced in the flues 8, 8 which will cause an inflow of air through the air supply flues 7 of the casing 5. The air entermg on opposite sides ofthe tank 3 is di- 7 rected by its curved or inclined bottom toward the center and by its slopes is evenly distributed against the surface of the plate to be etched, the air bubbling up through the openings formed in the plate 10. The air being sucked into the space that contains the'plate agitates the etching fluid and'the ebullitions effect a constant change of fluid against the plate so that new particles of the etching fluid are constantly brought in contact with the surface to be etched. The ebullition of the etching fluid upward against the resist on the submerged plate does not have the eflect of undercutting which is an incidentto a flow of, etching fluid over the plate as practised in etching with a tab that is rocked.

The constant passage of air through the etching fluid tends'to absorb the heat generated by the decomposition of the metal by The air as etching the'fumes which are given off are i Y carried by the suction fan or other means to a flue or outside of the etching room.

'When the plate has been etched the door is swung out to rest over the tub in an inclined position to be washed, waterbeing sprayed over the plate through the several perforated pipes, as indicated.

Having thus set forth our invention, we do not hold ourselves to any specific construction of apparatus, for the same may be readily modified, it being possible to obtain good results by forcing the air through the etching fluid, or by increasing the pressure upon the liquid beyond the plate, and the casing may be dispensed with at a point substantially above the dotted line 55, and in such modified form the flues 8, 8 will be confan.

Vi e claim. I

1. In an etching apparatus, a tank for etching fluid, means for effecting an ebullition of the etching fluid by the introduction of air into the etching fluid, means for maintaining a plate to be etched so that said plate will be maintained in a fixed position submerged in the etching fluid with the face to nected by apipe that extends to the exhaust etching fluid,means for introducing air into :the tank to effect an ebullition of'the etching fluid therein, a plate-holder which is maintainedin hinged engagement with the tank'and is adapted to carry a plate so that the plate may be maintained face down-' ward and submerged in the etching fluid, and a perforated plate maintained in the tank submerged in the etching fluid below the face of the plate to beetched and above the bottom of the tank. a

8. In anetching apparatus," a tank for etching fluid, a plate-holder maintained in such pivotal relation fto the tank that a plate maintained by the; plate-holder may be positioned below the surface of the etching fluid in the tank with its face down:

ward, means associated with the plate holder for moving said plate-holder to position the same in or out of the etching fluid, a perforated plate maintained within the tank for etching fluid and positioned 'above the bottom of the tank and below the face of the plate that is maintained by the plateholder when said plate is submerged in the etching fluid. I

4:. In an etching apparatus, a container for etching fluid, a. plate support associated therewith to maintain a vplate within said container, a partition that depends below the normal level of etching fluidin the container and means; for unbalancing the atmospheric pressure on opposite sides of the depending partition. I

5. In an etching apparatus, a container for etching fluid, a plate-support, which constitutes a partial closure for the container, flues associated with the plate-support and means for effecting greater pressure in one of the flues than in the other; sufficient to aerate the etching fluid in the container.

6. In an etching apparatus, a tank for etching fluid, a perforated plate maintained within the tank, a pivotal support for a plate to be etched maintained so that the plate to be etched will be maintained above the plane and out of contact with the perforated plate, and means for reducing the atmospheric pressure above a portion of the etching fluid in the tank to effect an ebullition of aportion of the etching fluid inthe tank.

, 7. In an etching apparatus, a tank for etching fluid, partitions that extend into the tank below the level of fluid contained therein, a perforated plate maintained by the partitions, a plate carrier adapted to maintain aplate to be etched so that said plate will be submerged in the fluid above the perforated plate and means for effecting a flow of'air through theperforations in the plate. 7 8. An etching apparatus comprising a tank for etching fluid, a casing associated with the tank and provided with flues, a combined plate carrier; and cover for the tank and means for exhausting the air above the etching fluid about the plate to effect an aeration of the etching fluid in the tank so that globules of air produced in the etching fluid. are caused to impact against the plate to be etched. 9. An etching apparatus provided with air inlet and outlet flues and a part having an opening therethrough, a tank for etching fluid, a combined closure for the opening and a plate support, means for effecting a flow of air into and through the etching fluid in the tank'to aerate the same and meansbetween the plate to be etched and the bottom of thetank for equalizing the impact of the aerated fluid against the surface to be etched. I 1 I 10. An etching apparatus comprising a tank for etching'fluid, a casing maintained above the tank and provided with side flues, one of the lines extending below the level of the fluid in the tank and the other terminating above the level of the fluid in the tank, a perforated wall maintained horizontally in the tank, a cover for the tank, means for connecting a plate to be etched to the cover and appropriate means for creating a partial vacuum above a part of the etching fluid in the tank. I

. 1. In an etching apparatus, a tank the bottom thereof being constructed to provide a raised central portion and portions between the raised central portion and the sides, a casing constructed to provide air exhaust flues the lower ends of which are below the fluid level of the tank, an exhaust fan'connected with the exhaust flues, means,

for maintaining a .plate to be etched submerged in fluid placed the tank, and means associated with the apparatus for washing the etching fluid from the surface of the plate when the plate is positioned beyond the tank for the etching fluid.

12. In an etching apparatus, a tank for etching fluid, a plate-holder or carrier maintained in hinged relation with the within the tank below the plate to be etched and means for reducing the atmospheric pressure above a portion of the etching fluid operative to draw} air through the etching fluid and through the'perforations in the perforated plate, to effect an ebullition and aeration of the etching fluid in the tank and a movement of bubbles over the face of the plate to be etched.

14. In an etching apparatus, a-tank for etching fluid, a rock shaft associated with the tank, aplate-holder carried by -a .rock shaft maintained to position the shaft out of contact with the'etching fluid and to position the plate that is associated with the plate-holder submerged in etching fluid con tained in the tank, means for moving the rock shaft to position the plate in an inclined position face upward, and means for washing the plate when in an inclined posi tion. Y

15. In an etching apparatus, a container for etching fluid, a plate to be etched associated with a plate carrier to be maintained thereby submerged in the etching fluid, means for introducing air into and through the etching fluid and diffusing the same prior to impact with the surface of the plate and means for carrying the vitiated air from the apparatus.

16. Inan etching apparatus, a container for etching fluid, a plate-holder associated therewith to constitute a cover for the container for etching fluid and to maintain a plate attached to the plate-holder submerged within the etching fluid in the container, and means for exhausting the air from a portion of the surface of the etching fluid to effect an ebullition of the etching fluid in the container below the plate.

17. In a device for the purpose set forth, a container for etching fluid, a support'for the object to be etched and a closure for the container for etching fluid which is pivotally associated with said container, means for reducing the air pressure about the support sufficient to effect an ebullition of the etching fluid in the container such means also serving to carry away the vitiated air.

18L In an etching apparatus, a tank for etching fluid, aplate-support or carrier pivotally maintained by means associated with the tank whereby a plate attached to the support may be maintained submerged face down in the etching fluid and when so positioned the plate support or carrier will serve as a cover for the tank, a perforated plate maintained within the tank below the plate to be etched so that the plate will not engage therewith, and means for effecting an ebullition of the etching fluidin the tank.

19. An etching apparatus comprising a tank adapted to contain an etching bath,

alined bearings for a rock shaft associated with the tank, a rock shaft maintained by the bearings," a plate carrier maintained by the'rook shaft, manually operative means for turning the rock shaft to move the plate carrier with its attached plate toahorizontal positionbeneath the level of the bath, and

means for maintainingthe plate carrier and its attached plate in a horizontal position. Q

20. An etching apparatus comprising a central portion which extends upward to i provide side portions below the raised central portion of the tank, a plate holder appropriately'associated with-the tank to be placed in horizontal'position over the etching fluid and to maintain a plate carried thereby submerged in the etching fluid and to provide a partial cover for the tank, a perforated plate maintained within the tank above the plane of the raised central portion thereofand below the plane of the plate to be etched, and aero-dynamic means for ebulli tion of the etching fluid in the tank.

22. In an etching apparatus, a tank for etching fluid, a plate carrier associated with the etching tank and constructed to provide means whereby a plate carried thereby may be maintained submerged in'the etching fluid with its face downward and to be positioned beyond the tank for the etching fluid in an inclined position with its face upward, and means associated with the etching apparatus for 'washing'the plate when maintained beyond the tank and in an inclinedposition.

23. In an etching apparatus, a tank for etching fluid, means associated with the tank for effecting an ebullition by aerification of the etching fluid in the tank, means for-maintaining aplate to be etched submerged face downward in the etching fluid and adjacent to the surface thereof, means for closing the tank except as to the entrance of air and the exit of fumes, and a flue which communicates with the tank and enters'the same at a point above the surface of the etching fluid.

24. In an apparatus for etching metal plates, a tank for etching fluid having associated therewith means for introducing air into the etching fluid to effect an ebullition of the etching fluid in the tank, a perforated plate submerged in the etching fluid below a plate to be etched, a closure for the tank,

means for maintaining aplate to be etched face downward and submerged in the etch ing fluid and in a fixed position relative to the normal level of the fluid in the tank, and a conduit which communicates with the tank for the exit of fumes from the tank.

' 25. In an etching apparatus, a tank adapted to contain etching fluid, means associatedwith the tank for maintaining a plate to be etched in a fixed position with its face downward and submerged in the etching fluid, means for introducing air into the etching fluid below the plate to be etched to effect an ebullition of the etching fluid and an impact of the bubbles against the under surface of the plate, a closure for the tank, and a flue or conduit which communicates with'the interior of the tank above the normal level of the etching fluid for the exit from the tank of fumes generated therein.

Copies of this patent may be obtained for 26. In an etching apparatus, a tank for etching fluid, a plate carrier associated with the tank to maintain a plate to be etched in a horizontal position and submerged in the etching fluid, means for introducing air into the etching fluid and means maintained above the plane of the entrance of air into the etching fluid for dispersing the bubbles formed prior to their contact with the plate to eifeot a distribution of the bubbles over the under surface of the plate, a closure for the tank, and an exit flue for the fumes produced in etching.

LOUIS E. LEVY. HOWARD S. LEVY.

Witnesses:

ISABEL W. BARNES, CADWALLADER O. HUGHES.

five cents each, by addressing the Commissioner of Patents,

Washington, D. 0. 

